Zn + 2HCl= ZnCl2 + H2
200*0.2=40гр HCl
x=40*22.4/73=12.2л
x=40*2/73=1.09гр H2
a) 2H2S+SO2=3S+2H2O
б)H2S+Br2=S+2HBr
в) H2S + HNO3 (конц.) =S+NO2+H2O